Medieval Bavaria once stretched deep into what is now Austria
Today's Bavaria is a German state, but the early medieval duchy ran along the Danube to the Hungarian frontier and over the Brenner Pass into South Tyrol. Over centuries it was carved up: Carinthia split off in 976, Austria became its own duchy by 1156, and Salzburg and Tyrol drifted away too.
The first duchy took shape in the 6th century as a frontier zone of the Frankish Merovingian kingdom. The chronicler Jordanes placed the Bavarii east of the Swabians around 551 to 555, and the first known duke, Garibald I of the Agilolfing family, ruled from 555 as a largely self-governing vassal, with Regensburg, the old Roman fort of Castra Regina, as the ducal seat. Christian missionaries built the church structure: Saint Rupert founded the see of Salzburg in 696, probably after baptising Duke Theodo, and in 798 Pope Leo III made Salzburg the head of a Bavarian church province.
Independence ended under the Carolingians. Duke Tassilo III tried to preserve it through an alliance with the Lombards, but when Charlemagne conquered Lombardy, Tassilo fell and was deposed in 788. Frankish prefects took over, and Bavaria became the launch pad for Charlemagne's campaign against the Avars from 791, which pushed the frontier from the Enns river to the Vienna Woods and created an Eastern March, the seed of later Austria.
When the Carolingian realm split at the Treaty of Verdun in 843, Bavaria went to East Francia, and it served as the power base for Arnulf of Carinthia, elected German king in 888. Hungarian raids then hammered the region; tradition says a Bavarian army was all but annihilated at Pressburg in 907. Arnulf the Bad rallied what remained and became duke, but German kings repeatedly clipped the dukes' wings. Otto I installed his own brother in 948, and only Otto's victory at Lechfeld in 955 ended the Hungarian threat.
Later rivalry between the Welf and Hohenstaufen dynasties shaped the duchy's fate. Emperor Frederick Barbarossa stripped Henry the Lion of his fiefs and in 1180 handed Bavaria to the House of Wittelsbach, which kept it until 1918. Its rulers became prince-electors in 1623, during the Thirty Years' War, and kings courtesy of Napoleon in 1806.
Source: Duchy of Bavaria
